Electronics Forum / Electronics / October 2005

I am trying to make an underwater diving light. Does anyone know where I can
find a circuit design to power an HID bulb?
Thanks
Henry

Gidday All,
                at last an affordable easy to use quality Spectrum
Analyser with excellent performance.
Recently arrived from China...  these Spectrum Analysers are BRAND

Here we go. Consider a resistor and a zener connected as a shunt regulator
between +ve and -ve supply rail. The resistor is sized so that a safe
no-load current of, say, 25mA passes through zener. Naturally, we measure
the nominal zener voltage or thereabouts at the point where ...

I need a bunch of stand-offs (spacers?), for some PCBs that *don't*
have holes in them. So I guess they need to somehow hold the boards at
the sides? Also, they need to be of the adhesive base sort because of
the casing they're going into. I've tried my usual places, RS, Maplin

I have just purchased two  Cat 5e  A type patch cords of different length
and manufacture.Whilst both are wired identically (straight through,1 to 1
etc.),I notice  the colour codes used are different,one following the 568A
code and the other following the 568B code.Could someone ...

Ok..
First, thank you for even reading this post, as I know I am not a regular
(infact I don't recall posting here ever before, though I might have).  That
being said.. onto the details.

Well I just got myself an ipod and wondering how to charge the batteries for
first time use.
Im sure that with Li-ion I can just do the standard charges making sure that
the first 3 charges are complete discharge/charge cycles.   then I can top

As I don't have the time or money (or knowledge) to design my own
electronics I'm taking an existing product and modifying it :-) It runs off
three 1.5V watch batteries in series. I'd like to replace this with a single
4.5V rechargable battery and charge it from a USB port. Does ...

brand

that

Ok..
First, thank you for even reading this post, as I know I am not a regular
(infact I don't recall posting here ever before, though I might have).  That
being said.. onto the details.

I work in the trailer manufacturing business.
We use LED tail-light clusters.
The modern truck/tractors utilise a computer system to perform diagnostics
on various systems within the rig. One of these is the lighting system.

Does anyone know a manufacture of a 70-0-70VAC transformer ? All the ones
listed in Farnell are 55-0-55 tops, Clairtronic only list upto 55V...
any ideas for anywhere which would make custom ones without breaking the
bank ?

Hello, Just look.
The theorem of magnetic shells by Gauss predicts a uniform magnetic field
across the diameter of a solenoid.  Measurement shows this to be false.  The
field is higher near the windings.

I am developing a "smart" alarm clock. I need to determine how to I
will generate the alarm sounds. The main requirement is the ability to
generate loud sounds and to vary the sound volume. One option is to use
a PIC18Fxx processor (already part of the circuit) to generate the

Does anyone know where I can find a schematic for a Pacemaker?  Any brand
will do, I'd just like to see what's so special about their circuitry that
would justify a cost of $10,000 dollars.
I know the medical field feels we owe them our lives, but you can get a